Technical Field
The present invention relates to a control device for an internal combustion engine having a turbocharger, and particularly relates to a control device for an internal combustion engine in which an abnormality of an exhaust-bypass valve, such as a waste-gate valve, is detected.
Background Art
In a conventional internal combustion engine having a turbocharger, a control device for the internal combustion engine is known, in which an abnormality of a waste-gate valve (hereinafter, referred to as a WGV) is detected. For example, in Japanese Laid-Open Patent Publication No. 2008-95587, a control device for an internal combustion engine is disclosed, in which an index value for indicating an increment of a supercharging pressure at an initial condition for supercharging the engine is obtained, and when the index value is lower than a predetermined reference value, it is judged that a closing-operation failures of the WGV is caused.
Moreover, in Japanese Patent Publication No. 5196036, a control device for an internal combustion engine is disclosed, in which it is judged that an operation abnormality of a WGV is caused or not caused in accordance with a pressure variation in an intake air pipe when an exhaust gas recirculation valve (ECR valve) is opened and the WGV is opened.